It makes plenty of sense.
Three shots is a VERY limited sample, and one case with a thicker neck can result in higher pressure/velocity. And .0001" (one 10/1000ths) in either bullet or bore diameter results in about 1000 psi difference in pressure.
Plus there's the difference in manufacturing lots of powder, plus umpteen other things, including temperature, primer, etc. etc. etc.
I agree it
could make sense, we've all seen things like this happen. On the face of it though it makes no sense and should produce one of those step back and scratch your head moments.
Just dropping from 150 to a 130 one would expect a little more velocity and a little less pressure at least until the laws of physics change. Accompanying that drop in bullet weight you you usually need to bump the charge a little to keep the pressure. Things that it might be he did not get if his test is repeatable.
Yes some guns max out at below book max. Yes temp can add some to the pot. Yes dimension tolerances can add some more.
But... what he got is not at all what I would expect. Especially given how the tests that I did with the 150s produced a very mild load.
It makes me wonder if this might be a side of LeverEvolution powder that goes with the little to no benefits accruing to many calibers with it. It makes me wonder enough to try to replicate it to see whether there is a characteristic of LeverEvolution powder that we might ought to be mindful of.
